How to find the size of Boot section from original firmware !?


I installed openwrt-ar71xx-generic-tl-wr710n-v2.1-squashfs-factory on TP-Link-WR710n_Ver2.1 device. but after installing I hadn't access to web user interface. I connected to device via SSH. I want to install original TPlink firmware again.

Problem: according to ,my tplink firmware (TP-Link-WR71n_Ver2.1) is contains word "boot". So I must to cut off parts of the image file before flashing.

Please help me to find the size for skip parameter in 'dd' command.

Links: #(Go to Discovery (How to find out) section)

Thanks in advance.

The cut off is only needed if you flash the tp link firmware with the sysupgrade command from within openwrt/lede.

The size of the boot part will be 128k.

dd if=fw_boot.bin of=fw.bin bs=1k skip=128

Which image have you installed?
Only stable releases did include the luci web interface by default.
The snapshots did not have a web gui, but could be installed with:

opkg update
opkg install luci
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Thanks you @juppin

I used information of below links:

I think the Open-WRT firmware has not installed completely/correctly.
Also I haven't internet connection in TPLink__TL-WR710N to run your commands (opkg update AND opkg install luci); because I'm in SSH and configs lost.
I have wlan0 interface (via ifconfig), but I haven't /etc/interfaces file. even I can't connect to my wifi network via: iw dev wlan0 connect WiFi-MAX-Net

please help me to repair or roll-back the original firmware and try to install another WRT firmware.

Thanks you

Take a look into for configuring network.
And for wireless configuration.

To setup wifi as client here an example for /etc/config/wireless

config wifi-device 'radio0'
	option channel '1' # The channel of your ap

config wifi-iface
	option device 'radio0'
	option mode 'sta'
	option ssid 'WLAN' # The ssid of your ap
	option bssid 'XX:XX:XX:XX:XX:XX' # The bssid of your ap
	option encryption 'psk2+ccmp'
	option key 'password'
	option network 'lan'
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Thanks you so much

I'll try it.

Why not flash from within your current running openwrt?

Upload this image with SCP (Windows: WinSCP) to your router to /tmp (ramdisk) and do:
sysupgrade -n /tmp/openwrt-18.06.0-rc1-ar71xx-generic-tl-wr710n-v2.1-squashfs-sysupgrade.bin

As i said, all stable releases did include a web interface by default... No need to get first back to stock fw.

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I'll try it. and I'll say you.
Thanks man.

Thanks Thanks.
But I have a question:
Which firmware is stable ?

  1. !!??
  2. !!??

the upgrade firmware is for Web-Interface!? Why after installing factory, I can't login to device via web-interface (WUI) !?

could I install my own HTML template on this device !?
Is it possible for all supported WRT devices !?

last question: how you found the the size/value of skip parameter for dd command. please help me.

Everything here is stable and everything here is build from master branch and not stable.

You could install your own template, but is not that easy to create a theme...
Take a look at here:

sysupgrade image is for upgrade from withing openwrt (sysupgrade command or luci web gui)
factory image is for flashing from stock / vendor firmware.

You can see the bootloader size on linux kernel log:
[ 0.740000] 0x000000000000-0x000000020000 : "u-boot"
0x20000 == 128kb

Because on non stable builds there is no web interface!

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